Fluoride compounds have been incorporated into dental topicals and into consumables for the prevention of tooth decay. This prevention is by virtue of such effects as strengthening of the enamel, suppression of the enzymatic action of bacteria which convert saccharids into acids and suppression of the propagation of microorganisms relating to the corrosion destruction of enamel and dentine. Studies have demonstrated that fluoride combines with hydroxyapatite, the crystalline structure of the teeth, to produce a modified crystalline structure which is more resistant to acid attack.
A wide variety of fluorides have been disclosed in the prior art, including sodium fluoride, indium fluoride, sodium monofluorophosphate, stannous fluoride, fluoroalkyl phosphates, and quarternary ammonium fluorides. These and other fluorides have been incorporated into gels, rinses, toothpastes, tooth powder, chewing gum and the like for topical application. Fluoride treatment can also be undertaken through consumables, fluoridated drinking water and fluoride tablets. It has been definitely established, on the basis of large studies in a number of communities that the fluoridation of water to a concentration of 1.0 ppm is a safe and practical public health measure. The resultant effect is 50-66% reduction in the incidents of dental carries in permanent teeth. It has also been demonstrated, in a 15 year study, that the administration of sodium fluoride in relatively small amounts during pregnancy resulted in almost complete elimination of dental carries in subsequently born children. (Glenn, Journal of Dentistry for Children, January 1980.)
Numerous patents have been issued which describe chewing gum with fluoride-containing salts: Arrick, et al. U.S. Pat. No. 4,563,345; Robyt et al. U.S. Pat. No. 4,228,150; Terta et al. U.S. Pat. No. 4,265,877; Goupil U.S. Pat. No. 4,284,650; Cornell U.S. Pat. No. 4,233,288; Bilotti et al. U.S. Pat. No. 3,075,884; Merckel et al. U.S. Pat. No. 2,627,493; and Merckel et al. U.S. Pat. No. 2,700,012. Each of these inventions have an improvement over the prior art, and each incorporate fluorides in different forms into chewing gums.
The ingestion of any significant amount of fluoride (as low as one gram of sodium fluoride) can produce consequences such as abdominal cramping and possible vomiting. As noted by U.S. Pat. No. 5,071,637 issued to Pellico, et al., the risk is noteworthy in flavored fluoride products which can be unintentionally swallowed in significant amounts. Therefore, the amount of fluoride used in a chewing gum is limited, yet effective.
However, the need for a composition which facilitates the optimal uptake of fluoride by teeth is apparent and has not been fulfilled by the prior art.